Vicious Cycle: Drought Threatens Amazon Forest, Speeds Global Warming

Fewer Trees = More Warming = Fewer TreesA 30-year study (!) involving 68 scientists from 13 countries just published in the prestigious journal Science reports bad news: the world's largest tropical rain forest is more sensitive to drought than previously thought, and the resulting loss of vegetation will have a greater-than-expected effect on carbon sequestration, and thus global warming. "Researchers said the total impact of the drought was an additional five billion tons of carbon dioxide in the atmosphere -- more than the combined annual emissions of Europe and Japan."

But it would be dangerous to just rely on how the Amazon forests look, because we might not easily notice the difference. What we need is quantitative tools to know if more or less carbon is absorbed.

"For years, the Amazon forest has been helping to slow down climate change. But relying on this subsidy from nature is extremely dangerous," said Professor Oliver Phillips of Britain's University of Leeds, the lead author of the study.

"If the Earth's carbon sinks slow or go into reverse, as our results show is possible, carbon dioxide levels will rise even faster. Deeper cuts in emissions will be required to stabilize our climate."